On Thu, Mar 04, 2021 at 03:33:30AM +0900, Masahiro Yamada wrote:
> This guarding is wrong. As Documentation/kbuild/llvm.rst notes, LLVM=1
> switches the default of tools, but you can still override CC, LD, etc.
> individually.
>
> BTW, LLVM is not 1/0 flag. If LLVM is not passed in, it is empty.
>
> Non-zero return code is all treated as failure anyway.
>
> So, $(success,test $(LLVM) -eq 1) and $(success,test "$(LLVM)" = 1)
> works equivalently in the sense that both are expanded to 'n' if LLVM
> is not given. The difference is that the former internally fails due
> to syntax error.
>
> $ test ${LLVM} -eq 1
> bash: test: -eq: unary operator expected
> $ echo $?
> 2
>
> $ test "${LLVM}" -eq 1
> bash: test: : integer expression expected
> $ echo $?
> 2
>
> $ test "${LLVM}" = 1
> echo $?
> 1
>
> $ test -n "${LLVM}"
> $ echo $?
> 1
>
> Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
Yes, there is not too much point of checking if $(LLVM) is set or not
because we already check for the other tools.
Reviewed-by: Nathan Chancellor <nathan@xxxxxxxxxx>
> ---
>
> arch/Kconfig | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/arch/Kconfig b/arch/Kconfig
> index 2bb30673d8e6..2af10ebe5ed0 100644
> --- a/arch/Kconfig
> +++ b/arch/Kconfig
> @@ -632,7 +632,6 @@ config HAS_LTO_CLANG
> def_bool y
> # Clang >= 11: https://github.com/ClangBuiltLinux/linux/issues/510
> depends on CC_IS_CLANG && CLANG_VERSION >= 110000 && LD_IS_LLD
> - depends on $(success,test $(LLVM) -eq 1)
> depends on $(success,test $(LLVM_IAS) -eq 1)
> depends on $(success,$(NM) --help | head -n 1 | grep -qi llvm)
> depends on $(success,$(AR) --help | head -n 1 | grep -qi llvm)
> --
> 2.27.0
>
